Apparatus for dismantling and assembling roll assemblies for a 4-high rolling mill

ABSTRACT

This disclosure is directed to dismantling and assembling operations for work rolls and/or backup rolls, which may include backup rolls with an additional pair of bearing chocks for backup roll bending facilities such as employed in a 4-high rolling mill. The apparatus disclosed includes a pair of extractor cars horizontally displaceable towards and away from each other at spaced-apart locations. Displaced at right angles between these cars is a roll carriage having support saddles for carrying in a horizontal spaced relation a worn roll assembly and a refurbished roll assembly. The roll carriage has stop means employed to align at different times the rolls carried by the saddles in relation to travel of the extractor cars. The extractor cars have guides to assure their mutual alignment with respect to each other and with respect to a roll supported by the saddles.

United States Patent [1 1 McGeeney et al.

[ APPARATUS FOR DISMANTLING AND ASSEMBLING ROLL ASSEMBLIES FOR A 4-I-llGH ROLLING MILL [75] :lnventors: William S. McGeeney, Pittsburgh;

George S. Trapp, Bethel Park; Leslie Zsamboky, Pittsburgh, all of Pa.

[73] Assignee: wean United, Inc., Pittsburgh, Pa.

[22] Filed: Apr. 24, 1972 [211 Appl. No.: 246,794

[52] U.S. Cl. 72/239, 29/200 [51] Int. Cl B2lb 31/08 [58] Field of Search 72/239, 238; 29/252,

[56] References Cited UNITED STATES PATENTS 3,577,758 5/1971 Adair 72/239 3,531,969 10/1970 Amino et al....

3,289,282 12/1966 Shaffer 29/200 D Jan. 1, 1974 [57] ABSTRACT This disclosure is directed to dismantling and assembling operations for work rolls and/or backup rolls, which may include backup rolls with an additional pair of bearing chocks for backup roll bending facilities such as employed in a 4-high rolling mill. The apparatus disclosed includes a pair of extractor cars horizontally displaceable towards and away from each other at spaced-apart locations. Displaced at right angles between these cars is a roll carriage having support saddles for carrying in a horizontal spaced relation a worn roll assembly and a refurbished roll assembly. The roll carriage has stop means employed to align at different times the rolls carried by the saddles in relation to travel of the extractor cars. The extractor cars have guides to assure their mutual alignment with respect to each other and with respect to a roll supported by the saddles.

15 Claims, 11 Drawing Figures PATENIEDJAH 1 I974 gv z.

FIG.

PATENTEUJAH 119M 3,782,161

SHEH MP 9 ISA-L FIG. 3

PATENTEDJAH I 1974 $782,161

sum 5 or 9 FIG. 5

PATENTEDJAH H974 3.782.161

sum 70? 9 PAIENIEDJAH 1 I974 SHEET 9 OF 9 has FIG. 9

F l G. 9 A

APPARATUS FOR DISMANTLING AND ASSEMBLING ROLL ASSEMBLIES FOR A d-HIGH ROLLING MILL This invention relates to an apparatus for handling and manipulating roll assemblies, inc l u d ing the component parts thereof, employed-in a 4-high rolling mill, and, in a specific instance, a rolling mill incorporating means for applying bending forces to extended journals of the backup rolls. More particularly, the present invention is adapted to be employed for dismantling and assembling each of the roll assemblies which are removed from such arolling mill for servicing.

Advancements in rolling mill technology include the concept of applying bending forces to extended. journals of the backup rolls of a 4-high rolling mill to control in a predetermined manner the roll deflections which inherently occur during the operation of the rolling mill. Certain forms of the necessary apparatus to carry out this concept, known in the art as backup roll bending, are disclosed in U. S.Pat. Nos. 3,250,105; 3,364,715; and 3,373,589. It is important with respect to the present invention that the apparatus employed to apply the backup roll bending forces includes an outboard bearing chock assembly mounted on each extended journal of the backup rolls. These outboard bearing chock assemblies are each spaced from other bearing chock assemblies mounted on the journals of the backup roll for rotatably supporting the backup rolls in the conventional manner within the rolling mill housing.

It is a present-day practice for the production of highquality metallic strip or plate to change the various roll assemblies in the mill stands after selected intervals of mill production. Rolling mil] roll changing is usually semblies twice a week. In a recently designed 4-high plate mill, the rolls are scheduled for replacement in the mill stand on the basis of changing the pair of work roll assemblies once each week and changing the pair of backup roll assemblies every four weeks. After a roll changing operation is completed, the worn roll assemblies which have been removed from the rolling mill are transported to a designated-area, such as a roll shop, where the roll assemblies are dismantled to their major component parts. These component parts are inspected and repaired, if necessary, and then reassembled on a refurbished roll to form a replacement roll assembly for future use in the rolling mill.

With regard to the aforementioned 4-high plate roll v ing mill, it is significant to appreciate the size and weight of the roll assemblies employed therein. The mill stand is designed to incorporate backup roll bending and it is capable of producing 190 incheswide plate. When removed from'the mill stand, each of the work roll assemblies will measure in excess of 26 feet long, while each backup roll assembly will measure in excess of 38 feet and weigh 325 tons.

In order to reduce the capital investment required for facilities to handle and manipulate these roll assemblies, including their various bearing chocks and other component parts during the dismantling and assembling operations, the facilities must accommodate at different times each of the work roll assemblies and each of the backup roll assemblies for a given rolling mill installation. Such facilities preferably must accommodate all the roll assemblies from a number of mill stands including a rolling mill stand incorporating backup roll bending apparatus. Known prior art has not satisfactorily met each of the foregoing requirements principally due to an inherent and traditional lack of uniformity in regard to the over-all dimensional size and configuration of the bearing chocks associated with each of the work roll assemblies and the backup roll assemblies. Compounding this lack of uniformity are the differences in the diameters of the work roll and backup roll. As a general rule, the backup rolls are much larger in diameter and the bearing chocks thereof are dimensionally larger in comparison with the work rolls and their bearing chocks. In view of the substantial size and weight of each roll assembly, the handling and manipulating apparatus must be constructed in a robust manner to withstand and support the forces and weight encountered during dismantling and assembling operations. These operations additionally demand critically precise alignment and movements in order to avoid possible damage to bearings, journal support surfaces for the bearings, drive coupling members and other parts of the roll assembly in order to assure an economically successful operation of the facilities. ln this regard, an important consideration is the time and labor required for mechanized dismantling of bearing chocks and other parts from a roll assembly, as well as the assembling operations, to form a roll assembly for reuse in the rolling mill.

It is an object of the present invention to provide an apparatus for dismantling and assembling at different times both work roll assemblies and backup roll assemblies employed in a 4-high rolling mill.

It is another object of this invention to provide an apparatus for dismantling and assembling a roll for use in a rolling mill or the like wherein the roll assembly has at least two pairs of bearing chocks forming part of a roll bending means.

It is a further object of the present invention to provide an apparatus for dismantling and assembling bearing chocks and couplings on work rolls and, alternatively, dismantling and assembling the bearing chocks from a backup roll assembly designed for use in a 4- high rolling mill incorporating backup roll bending means.

It is a further object of the present invention to provide a roll support carriage having position indexing means and a bearing chock extractor car having guide means, which carriage and car are constructed and arranged to provide precise interrelated alignment and movements incident to dismantling and assembling bearing chocks from a roll assembly.

These features and advantages, as well as others, will be more fullyunderstood when the following description is read along with the accompanying drawings, of which:

FIG. 1 is a plan view of an apparatus embodying the features of the present invention for dismantling and assembling a backup roll assembly or a work roll assembly,-

FlG.'2.is an elevational view taken along lines "-11 of FIG. 1,

FIG. 3 is an elevational view taken along lines IIIIII OF FIG. 1,

FIG. 4 is an enlarged elevational view of the extractor car shown at the right-hand side of FIG. 2,

FIG. 5 is an end elevational view of the extractor car illustrated in FIG. 4 taken along lines IV-IV of FIG. 4

FIG. 6 is a sectional plan view of the extractor car taken along lines VI-VI of FIG. 2,

FIG. 7 is a sectional view taken along lines VII-VII of FIG. 6,

FIGS. 8a and 8b are each partial sectional views taken along lines VIII-VIII of FIG. 6 and illustrating, in FIG. 8a, an upper backup roll chock supported by an extractor car and, in FIG. 8b, there is illustrated the lower backup roll chock supported by the same extractor car,

FIGS. 9a and 9b are each partial sectional views similar to'FIGS. 8a and 8b, except that FIG. 9a illustrates an upper work roll chock being supported by the extractor car, and FIG. 9b illustrates a lower work roll chock being supported by the extractor car.

FIGS. 1, 2 and 3 illustrate an apparatus embodying the features of the present invention for dismantling anfigsaabimg the roll assembhs employed in?? high rolling mill. This apparatus consists of three major components, namely, a roll assembly carriage 10, a right-hand extractor car 11, and a left-hand extractor car 12.

The roll carriage 10 has a first pair of saddles 13 with V-shaped roll engaging surfaces 13a supported in an aligned, spaced-apart relation upon beams 14 forming part of the roll carriage. A second pair of saddles 15 with V-shaped roll engaging surfaces 15a are secured in an aligned, spaced-apart relation upon the beams 14 at a predetermined spaced location from the saddles 13 whereby, as illustrated in FIG. 3 for example, a worn backup roll assembly 16 is supported by its roll face on the saddles 13 and a refurbished backup roll 17 is supported by its roll face on the saddles 15. The V-shaped roll engaging surfaces 13a and 15a maintain a constant predetermined spacing of the rotational axes of the rolls they support irrespective of their body diameters. Thus, the relative axial spacing of work rolls will be the same as larger diameter backup rolls. The carriage 10 further includes spacer members 18 and a spacer plate 19 for rigidly interconnecting the beams 14 in their spaced-apart relation. As best shown in FIG. 3, to the underside of each beam 14, directly beneath each saddle, there is secured a rollercage 21 having a radial recess for receiving a roller 22 which is carried by a radial recess formed in a truck assembly 23. The truck assembly 23, being well known in the art per se, includes a pair of rotatably mounted wheels 24 which are supported for traverse movement along a pair of parallel, spaced-apart rails 25 secured in a pit-like recess 26 formed in the foundation. A piston and cylinder assembly 27 is secured to the floor of the recess 26 between the rails 25. The rod end 27a of the piston and cylinder assembly 27 is connected to the lower end of a downwardly extending bracket 28 which is welded to the spacer plate 19. A vertically disposed reinforcement beam 29 is situated at each end of the rails 25 in a manner that the beams 29 are substantially embedded in the concrete which defines upstanding end walls of the pit 26. Each beam 29 has an exposed face to which there is secured a shim pack 31 at the upper end of the beams 29. A stop block 32 is attached to each end of the carriage beams 14. By selective use of the individual shims making up the shim packs 31, the carriage 10 is precisely located on the rails 25 to consistently locate the rotational axis 16a of the worn backup roll assembly into a predetermined axial alignment with the extractor cars 11 and 12. When the carriage 10 is shifted to the phantom line position, as one views FIG. 3, the use of the shim packs 31 assures the predetermined axial alignment between the rotational axis 17a of the refurbished backup roll 17 and the extractor cars 11 and 12. It is important to note that the foregoing description of the apparatus and its relationship to backup rolls applies with equal effect to the normally smaller diameter work rolls insofar as this aspect of the present invention is concerned.

Before further describing the extractor cars 11 and 12, attention is directed to the worn backup roll assembly 16 which is constructed in a manner to execute the concept of backup roll bending, and it is best illustrated in FIGS. 2, 3 and 4. The backup roll assembly 16 comprises a roll body 1612 from which there extends at each end ajournal 16c. A main bearing chock assembly 16d is mounted on each journal adjacent the roll body. An outboard bearing chock 16e is mounted to the journal 16c at its outboard end where it is held in a spaced relation from the bearing chock 16d by spacer links 16f. Each side of the bearing chock 16d is machined with a threaded recess for securing a lifting lug 16g. These lugs are attached to the chocks 16d after the backup roll assembly has been removed from the rolling mill whereby the lugs provide surfaces for attaching a sling from a crane to transport the roll assembly to and from the saddles 13. These lugs are further utilized to facilitate removal of the bearing chocks 16d in a manner to be more fully described hereinafter.

Attention is now directed to the extractor car 11 in which regard the following description is given for the purpose of illustrating and describing the details and features of the construction of both extractor cars 11 and 12 since both of these cars are constructed in an identical manner and they may be interchangeably located, if desired, with respect to the roll carriage 10. In view of this identical construction, the description and reference numerals applying to the extractor car 11 apply with equal effect to the extractor car 12, except as otherwise noted. 1

The extractor car 11, as shown in FIGS. 1, 2, 4 and 5, includes a frame 33 having two pairs of rotatably mounted wheels 34 which are arranged in a spacedapart relation for supporting engagement with similarly spaced-apart rails 35. The rails 35 are secured in a continuation of the pit 26. A pair of-spaced-apart rails 350 are provided to support the extractor car 12. A piston and cylinder assembly 36 secured in the pit has its rod end 37 connected to the car frame 33 for traversing the car 11 along the rails 35 in a direction normal to the direction of displacement of the roll carriage 10. More particularly, the rails 35 are so situated with respect to the roll carriage 10 that the extractor car 11 is symmetrically located with respect to the rotation axis 16a of the worn roll assembly 16 and, when the roll carriage is caused to assume the phantom line position shown in FIG. 3, the extractor car 11 is symmetrically located with respect to the rotational axis 17a of the refurbished roll 17. In order to consistently maintain this relationship, according to one of the features of the present invention, as best shown in FIGS. 1 and 5, there is provided an elongated guide bar 38 secured to the foundation in a spaced parallel relation to the rails 35 adjacent the roll carriage l0. Secured to the extractor car frame 33 is a downwardly extending guide block 39 having a rectangularly shaped slot 41 dimensioned to tightly receive therein the guide bar 38.

As shown in FIGS. 4, 5, 6, and 7, the extractor car frame 33 has upwardly extending, spaced-apart support members 42 and 43, each having a vertically extending recess into which there are secured wear strips for receiving in guided relationship vertical arms 44 and 45, respectively, which are joined together at their lower ends by a platen 46 to form a structure defined as a U- shaped elevator 47. As shown in FIG. 5, the arms 44 and 45 are spaced from each other at a distance slightly greater than the over-all width of the bearing chock 16d for the backup roll. The elevator 47 is vertically displaceable by a piston and cylinder assembly 48 which has trunnion mountings 48a on the frame 33.

The rod end of the piston and cylinder assembly 48 is secured by a threaded nut 48b to the center of the elevator platen 46. The platen 46 has a hollowed-out central portion 49 from which spaced-apart dowel rods 51 and 52 project upwardly. The hollowed-out portion 49 terminates at symmetrically arranged projecting ribs 53. A deep recess 54 extends into the platen 46 between each rib 53 and the vertically extending wall of the arms 44 and 45.

As best shown in FIGS. 2 and 4, the elevator 47 includes a cradle-shaped support surface 55 which is formed into the top surface of the arms 44 and 45. A I

manually operated latch 56 is pivotally mounted by a pin 57 within a window 58 formed in each of the plates 42 and 43. Each of the arms 44 and 45 of the elevator 47 is formed with a window 59 dimensioned to correspond with the dimension of the window 58. Moreover, when the elevator is raised to a predetermined elevation, the windows 58 and 59 are aligned with each other, whereupon the latch 56 is positionable to an operative location shown in FIG. 9b, wherein the latch extends into the interior of the elevator. It is important to note that the pivotal mounting of these latches in relation to the center of gravity thereof is such that a definite manual force must be provided to overcome the natural tendency of the latch to remain in a given position.

FIGS. 2, 4, 6 and 7 illustrate further features of each extractor car 11 and 12 which relate to providing a sled 61 employed to facilitate dismantling and assembling of both a drive coupling mounted on one end of a work roll and an outboard bearing chock mounted on an extended journal of a backup roll. The sled 61 includes a slide plate 62 supported for horizontal movement by bearing surfaces 63 provided at each side of the extractor car frame 33. A piston and cylinder assembly 64 has a trunnion mounting 65 on the frame 33 and has its rod end attached to the slide plate 62 for displacing the sled 61 relative to the frame 33. The sled 61 supports a trunnion mounted piston and cylinder assembly 66 employed to vertically displace an appliance structure 67 independently of the elevator 47. As shown in FIG. 7, vertical plates 68 guide and support a piston 69 projecting downwardly from the appliance structure 67. The structure 67 takes the form of a two-compartment appliance wherein the first compartment consists of a series of tandemly arranged rollers 71 and a stripper plate 72 supported and arranged to partly encompass and support a coupling member during its displacement relative to a work roll. The second compartment of the structure 67 takes the form of a fabricated platen 73 having projecting thrust blocks 74 for establishing a driving engagement between the platen 73 and the outboard bearing chock 16c mounted on a backup roll.

FIG. 2 illustrates a jib crane 75 which is pivotally supported by the extractor car 11 between the elevator 47 and the sled 61 in a manner that it can be horizontally positioned to aid in dismantling and assembling parts for the roll assemblies.

The operation of the apparatus with respect to a backup roll assembly is carried out by first transporting the worn backup roll assembly 16 through the use of a crane and sling engaging the lugs 16 to position the assembly on the saddles 13. A refurbished backup roll is then deposited on the saddles 15 which has been illustrated and described with FIGS. 1, 2 and 3 of the drawings. The piston cylinder assembly 27 is operated to position the roll carriage, as shown in these drawings, into an abutting engagement with the shim pack 31. The elevators 47 and the appliance structure 67 on each extractor car 11 and 12 are lowered to a position such that, upon operation of the piston cylinder assembly 36, the extractor cars 11 and 12 are displaced toward the worn backup roll assembly. As this displacement continues, the guide bar 38 and guide block 39 are brought into a guiding relation to assure alignment be tween the rotational axis 16a of the backup roll assembly with the symmetrical center line of the extractor cars. After the extractor cars are positioned so that the elevators 47 are located directly beneath the main backup roll bearing chocks 16d, the appliance structure 67 is positioned directly beneath the outboard bearing chock Me by operation of the piston cylinder assembly 64. After the spacer links 16f have been removed, the piston cylinder assembly 66 is operated to elevate the platen 73 into supporting engagement with the outboard bearing chock 16e, following which the piston cylinder assembly 64 is operated to retract the sled 61, hence, also the outboard bearing chock 16c from the roll journal. The piston cylinder assembly 48 is then actuated to raise the elevator 47 until the cradle surface 55 receives in a horizontal driving relation the lugs 16g on the bearing block 16d within the cavity formed by the cradle surface. As shown in FIG. 8b, in this position of the elevator the bottom surface of the chock is supported on the rib 53 of the elevator platen in the case of the bearing chock for the lower backup roll, and, with respect to the upper backup roll chock as illustrated in FIG. 8a, the recess 54 in the platen 46 supports this chock via its downwardly extending leg 16h. The piston cylinder assembly 37 is then actuated to displace the extractor cars 11 and 12 and thereby displace the bearing chocks 16d in an axial direction from the backup roll. During this initial displacement of the cars, for example the first 30 inches, the cooperative relation of the guide block 39 and guide bar 38 maintains a precise alignment of the cars and the hearing chocks they support with respect to the axis of the roll. Since each extractor car carries a sled 61, when the cars are retracted to a point spaced from the end of the backup roll, the roll carriage 10 may then be shifted by the piston cylinder assembly 27 to bring the refurbished roll 17 into axial aligned relationship with the extractor cars through the agency of the shim packs 31. The refurbished roll is assembled with bearing chocks by following the above description in reverse, FIG. 9a illustrates use of the present invention for dismantling and assembling an upper work roll assembly which, as illustrated, includes a work roll 76 having bearing chocks 77 mounted on its journals in a conventional manner. FIG. 9b illustrates a lower work roll assembly which includes a lower work roll 78 having bearing chocks 79 mounted on its journals in the conventional manner. The top work roll bearing chock 77 is dismantled by first positioning the work roll assembly on the saddles l3 and a refurbished work roll on the saddles in a manner as previously described with respect to the backup roll. The elevator 47 is brought from its lowermost position by the piston cylinder assembly 48 into supporting engagement with the chock 77 whereby the chock is located within the hollowedout portion 49 of the platen and the dowel pins 52 are received in a recess formed in the bearing chock and thereby establish a positive driving relationship necessary to horizontally dismantle the bearing chock from the roll journal. With respect to the lower work roll assembly, as illustrated in FIG. 9b, the elevator 47 is raised to a position where the chock is supported within the U-shaped elevator on the ribs 53. In order to assure a positive driving relationship between the chock 79 and the extractor car 11, the latches 56 are manually rotated about the mounting pins to a position where they project through the window 59 in the elevator and engage projecting wings 80 forming part of the chock 79. Since both the top work roll and the bottom work roll have a roll coupling mounted on one end thereof, it is necessary, prior to extracting the chocks from the rolls, to remove the roll coupling. To perform this function, the sled 61 is positioned directly beneath the coupling by the piston cylinder assembly 64 whereupon the piston cylinder assembly 66 elevates the appliance 67 to a position where the coupling assumes a supporting relation with the series of tandemly arranged rollers 71 and the stripper plate 72 drivingly engages the inboard end of the coupling. The coupling is then extracted by operating the piston cylinder assembly 64 to horizontally displace the sled along the extractor car. After the coupling has been removed, the piston cylinder assembly 37 is actuated to retract the extractor car and remove the work roll chocks in an axial direction from the work rolls. These parts may then be inspected, repaired if necessary, and reassembled on a refurbished work roll which, when supported on the saddles 17, will require repositioning in a manner previously described with respect to a refurbished backup roll.

The over-all dimensional size of the bearing chock for the backup roll, as illustrated in FIGS. 8a and 8b, can be readily seen to be substantially larger when compared with the over-all dimensional size of the bearing chocks for a work roll, as illustrated in FIGS. 9a and 9b. Thus, the work roll chocks, due to their smaller over-all height and width, are received totally within the U-shaped elevator in a manner that a clearance exists between the work roll chocks and the vertical arms 44 and 45.

In accordance with the provisions of the patent statutes, we have explained the principle and operation of our invention and have illustrated and described what we consider to represent the best embodiment thereof.

We claim:

1. A dismantling and assembling apparatus in combination with a roll assembly from a rolling mill for processing strip material and the like, said roll assembly including a roll with extended journals at each end and two pairs of bearing chocks arranged on said journals such that one chock of each pair is mounted on each journal, said apparatus comprising:

carriage means including saddle surfaces for supporting said roll assembly such that said pairs of bearing chocks are arranged in a horizontally spaced relation while mounted on said journals, first and second extractor cars engagable with each one of said pairs of bearing chocks mounted on said journal of said roll assembly for supporting said bearing chocks, 1

means for horizontally displacing said extractor cars to dismantle and assemble the bearing chocks from each of said journals,

each of said extractor cars being supported and arranged for opposed horizontal displacement in a plane parallel to the rotational axis of said roll assembly,

said extractor cars further including separate and independent platens for supporting each one of said bearing chocks, and

means for vertically displacing each of said platens into engagement with one of said bearing chocks while mounted on a journal of said roll.

2. An apparatus according to claim 1 wherein said carriage means further comprises saddle surfaces for supporting a refurbished roll in a parallel spaced relation from said roll assembly,

means for displacing said carriage means between said first and second extractor cars, and

carriage stop means for establishing predetermined displacement positions of said roll assembly and said refurbished roll in relation with said extractor cars.

3. An apparatus according to claim 2 further comprising:

guide means carried by each of said extractor cars for maintaining a mutually aligned relation between said extractor cars during initial displacement of said bearing chocks from said journals.

4. An apparatus according to claim 3 further comprising wheels rotatably mounted on each of said extractor cars for supporting said cars during horizontal displacement thereof.

5. An apparatus for dismantling at different times the bearing chocks from a pair of work roll assemblies and a backuflroll assembly employed in a 4-high rolling mill wherein a bearing chock for each of said work roll assemblies and said backup roll assembly are characterized as to size by different over-all transverse dimensions when said assemblies are horizontally supported,

saddle means for supporting in horizontal planes at different times a work roll assembly and said backup roll assembly,

support means including load bearing surfaces constructed and arranged for engaging the bearing chocks of said backup roll assembly,

said support means further including a horizontally arranged platen having an upper surface defining a plurality of load bearing surfaces,

each of said last named load bearing surfaces being constructed and arranged for engaging at different times a bearing chock for each of said work roll assemblies,

elevating means for causing relative vertical displacement between said load bearing surfaces with respect to a different one of said bearing chocks, and

means associated with said support means for horizontally displacing said load bearing surfaces relative to said saddle means.

6. An apparatus according to claim wherein said support means further include:

a pair of vertically extending arms secured at their lower ends to said platen in a spaced-apart relation to define a U-shaped elevator,

said elevator being constructed to carry at different times a bearing chock from said work roll assemblies and said backup roll assemblies.

7. An apparatus according to claim 6 wherein said elevator further includes drive members for interlocking horizontal drive engagement with each of said bearing chocks.

8. An apparatus according to claim 7 further comprising:

lifting lug means secured to each bearing chock for said backup roll assembly, and

cradle-shaped surfaces carried by said vertically extending arms for engaging said lifting lugs in a horizontal driving relation.

9. An apparatus according to claim 7 further comprising:

latch means pivotally mounted for projecting into the area defined by said U-shaped elevator to engage in a horizontal driving relation a bearing chock for one said work roll assembly.

10. An apparatus according to claim 6 wherein said support means further includes:

first and second extractor cars supported for opposed horizontal displacement in an aligned relation,

each of said extracting cars having vertical guides for said U-shaped elevator, and

said elevating means including a piston and cylinder assembly for vertically displacing said elevator into engagement with one of said bearing chocks.

11. An apparatus according to claim 10 wherein said work roll assemblies each include a drive coupling member mounted on one end thereof, at least one of said extractor cars further comprising:

a carriage including a roller support for engaging said drive coupling member,

means for elevating'said roller support into engagement with said drive coupling; and

horizontal displacement means connected to said carriage for dismantling said drive coupling from said work roll assemblies.

12. An apparatus according to claim 10 wherein said saddle means further comprises:

a roll carriage having saddle means for supporting a refurbished roll in a parallel spaced relation from a roll assembly when supported by said saddle means,

means for displacing said roll carriage between said first and second extractor cars, and

carriage stop means for establishing predetermined displacement positions of said refurbished roll assembly in relation to said extractor cars.

13. An apparatus according to claim 12 further comprising guide means carried by each of said extractor cars for maintaining a mutual aligned relation between said extractor cars during initial displacement thereof to dismantle each bearing chock from a journal of one of said roll assemblies.

14. An apparatus for dismantling a bearing chock mounted on a journal of a rolling mill roll assembly, comprising:

a carriage including roll assembly support saddles for positioning said roll assembly with its axis of rotation contained in a horizontal plane,

an extractor car having means for engaging and supportinga bearing chock while mounted on a journal of said roll assembly,

means for horizontally displacing said extractor car in a direction parallel with said axis of rotation,

extractor car guide means for maintaining said extractor car in aligned relation with said roll assembly during initial displacement of a bearing chock from said journal of said rolling mill roll assembly,

additional roll support saddles for positioning a refurbished roll on said carriage in a spaced parallel relationship to said rolling mill roll assembly,

means for horizontally displacing said carriage in a direction normal to the displacement of said extractor car, and

carriage stop means for positioning said refurbished roll in a predetermined position with respect to said extractor car.

15. An apparatus according to claim 14 further comprising:

an additional extractor car having means for engaging and supporting a bearing chock while mounted on a second journal of said roll assembly, and

means supporting said additional extractor car in a mutually aligned relation with said extractor car for relative displacement from said carriage.

* a: a l 

1. A dismantling and assembling apparatus in combination with a roll assembly from a rolling mill for processing strip material and the like, said roll assembly including a roll with extended journals at each end and two pairs of bearing chocks arranged on said journals such that one chock of each pair is mounted on each journal, said apparatus comprising: carriage means including saddle surfaces for supporting said roll assembly such that said pairs of bearing chocks are arranged in a horizontally spaced relation while mounted on said journals, first and second extractor cars engagable with each one of said pairs of bearing chocks mounted on said journal of said roll assembly for supporting said bearing chocks, means for horizontally displacing said extractor cars to dismantle and assemble the bearing chocks from each of said journals, each of said extractor cars being supported and arranged for opposed horizontal displacement in a plane parallel to the rotational axis of said roll assembly, said extractor cars further including separate and independent platens for supporting each one of said bearing chocks, and means for vertically displacing each of said platens into engagement with one of said bearing chocks while mounted on a journal of said roll.
 2. An apparatus according to claim 1 wherein said carriage means further comprises saddle surfaces for supporting a refurbished roll in a parallel spaced relation from said roll assembly, means for displacing said carriage means between said first and second extractor cars, and carriage stop means for establishing predetermined displacement positions of said roll assembly and said refurbished roll in relation with said extractor cars.
 3. An apparatus according to claim 2 further comprising: guide means carried by each of said extractor cars for maintaining a mutually aligned relation between said extractor cars during initial displacement of said bearing chocks from said journals.
 4. An apparatus according to claim 3 further comprising wheels rotatably mounted on each of said extractor cars for supporting said cars during horizontal displacement thereof.
 5. An apparatus for dismantling at different times the bearing chocks from a pair of work roll assemblies and a backup roll assembly employed in a 4-high rolling mill wherein a bearing chock for each of said work roll assemblies and said backup roll assembly are characterized as to size by different over-all transverse dimensions when said assemblies are horizontally supported, saddle means for supporting in horizontal planes at different times a work roll assembly and said backup roll assembly, support means including load bearing surfaces constructed and arranged for engaging the bearing chocks of said backup roll assembly, said support means further including a horizontally arranged platen having an upper surface defining a plurality of load bearing surfaces, each of said last named load bearing surfaces being constructed and arranged for engaging at different times a bearing chock for each of said work roll assemblies, elevating means for causing relative vertical displacement between said load bearing surfaces with respect to a different one of said bearing chocks, and means associated with said support means for horizontally displacing said load bearing surfaces relative to said saddle means.
 6. An apparatus according to claim 5 wherein said support means further include: a pair of vertically extending arms secured at their lower ends to said platen in a spaced-apart relation to define a U-shaped elevator, said elevator being constructed to carry at different times a bearing chock from said work roll assemblies and said backup roll assemblies.
 7. An apparatus according to claim 6 wherein said elevator further includes drive members for interlocking horizontal drive engagement with each of said bearing chocks.
 8. An apparatus according to claim 7 further comprising: lifting lug means secured to each bearing chock for said backup roll assembly, and cradle-shaped surfaces carried by said vertically extending arms for engaging said lifting lugs in a horizontal driving relation.
 9. An apparatus according to claim 7 further comprising: latch means pivotally mounted for projecting into the area defined by said U-shaped elevator to engage in a horizontal driving relation a bearing chock for one said work roll assembly.
 10. An apparatus according to claim 6 wherein said support means further includes: first and second extractor cars supported for opposed horizontal displacement in an aligned relation, each of said extracting cars having vertical guides for said U-shaped elevator, and said elevating means including a piston and cylinder assembly for vertically displacing said elevator into engagement with one of said bearing chocks.
 11. An apparatus according to claim 10 wherein said work roll assemblies each include a drive coupling member mounted on one end thereof, at least one of said extractor cars further comprising: a carriage including a roller support for engaging said drive coupling member, means for elevating said roller support into engagement with said drive coupling; and horizontal displacement means connected to said carriage for dismantling said drive coupling from said work roll assemblies.
 12. An apparatus according to claim 10 wherein said saddle means further comprises: a roll carriage having saddle means for supporting a refurbished roll in a parallel spaced relation from a roll assembly when supported by said saddle means, means for displacing said roll carriage between said first and second extRactor cars, and carriage stop means for establishing predetermined displacement positions of said refurbished roll assembly in relation to said extractor cars.
 13. An apparatus according to claim 12 further comprising guide means carried by each of said extractor cars for maintaining a mutual aligned relation between said extractor cars during initial displacement thereof to dismantle each bearing chock from a journal of one of said roll assemblies.
 14. An apparatus for dismantling a bearing chock mounted on a journal of a rolling mill roll assembly, comprising: a carriage including roll assembly support saddles for positioning said roll assembly with its axis of rotation contained in a horizontal plane, an extractor car having means for engaging and supporting a bearing chock while mounted on a journal of said roll assembly, means for horizontally displacing said extractor car in a direction parallel with said axis of rotation, extractor car guide means for maintaining said extractor car in aligned relation with said roll assembly during initial displacement of a bearing chock from said journal of said rolling mill roll assembly, additional roll support saddles for positioning a refurbished roll on said carriage in a spaced parallel relationship to said rolling mill roll assembly, means for horizontally displacing said carriage in a direction normal to the displacement of said extractor car, and carriage stop means for positioning said refurbished roll in a predetermined position with respect to said extractor car.
 15. An apparatus according to claim 14 further comprising: an additional extractor car having means for engaging and supporting a bearing chock while mounted on a second journal of said roll assembly, and means supporting said additional extractor car in a mutually aligned relation with said extractor car for relative displacement from said carriage. 